26 



THE OPAL SEA 



Disturb- 

 ances of 

 the level. 



rarily. The height of the Bed Sea is low- 

 ered or elevated as the northwest wind blows 

 the water out of the sea basin or not, the estu- 

 ary of the Rio de la Plata is continually vary- 

 ing in level with the direction of the wind; 

 and, indeed, it is a commonly observed happen- 

 ing for water to be wind-driven in or out of 

 almost all bays and harbors. But these again 

 are inequalities of a temporary character. 



There is a greater variation in the Indian 

 Ocean around the head of the Arabian Sea, 

 where the water is supposed to be drawn up and 

 out of the spherical by so much as three hun- 

 dred feet — it is computed by some scientists as 

 even more. This almost incredible elevation is 

 accounted for by the attraction of the Hima- 

 layas. Possibly the Andes, that stand with their 

 feet in the ocean, produce a similar effect upon 

 the waters of the Pacific ; but certainly the man 

 before the mast has never seen it, and the 

 navigator in the chart room has never made 

 note of it. Nor is there any great certainty 

 about the upward pull of the Himalayas. That 

 the hydrosphere is drawn out of the spherical 

 by earth-attraction, or flung up in equatorial 

 ridges by the spinning motion of the earth, is 

 something as yet quite problematical. 



The change of level brought about by the 



Effect of 

 earth's at- 

 traction. 



